From 84b6b469cfb65acc1b344ec92a1dd572bd99d9ac Mon Sep 17 00:00:00 2001
From: Philippe Houdoin <philippe.houdoin@gmail.com>
Date: Sun, 5 Apr 2026 23:53:47 +0200
Subject: [PATCH] libnetwork: add support for
 /boot/system/settings/network/nsswitch.conf

This open opportunity to use extra netresolv's nsswitch modules, like libnss_mdns.so,
for zeroconf .local names resolution.

Change-Id: If71fc47d7ab066e99daa97d453e70dddc3449f71
Reviewed-on: https://review.haiku-os.org/c/haiku/+/10667
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
Reviewed-by: nephele nephele <nep-git@packageloss.eu>
---
 .../libnetwork/netresolv/include/nsswitch.h   | 15 +++++++++
 .../libnetwork/netresolv/net/nsdispatch.c     | 33 +++++++++++++++++--
 2 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/src/system/libnetwork/netresolv/include/nsswitch.h b/src/system/libnetwork/netresolv/include/nsswitch.h
index 4266494ebf..e2961b2949 100644
--- a/src/system/libnetwork/netresolv/include/nsswitch.h
+++ b/src/system/libnetwork/netresolv/include/nsswitch.h
@@ -38,10 +38,20 @@
 
 #define	NSS_MODULE_INTERFACE_VERSION	0
 
+#ifdef __HAIKU__
+
+/* Yacc generated nsparser.y needs _PATH_NS_CONF for error reporting purpose */
+#undef _PATH_NS_CONF
+#define _PATH_NS_CONF	nsswitch_conf_file_path()
+
+#else
+
 #ifndef _PATH_NS_CONF
 #define _PATH_NS_CONF	"/etc/nsswitch.conf"
 #endif
 
+#endif
+
 #define	NS_CONTINUE	0
 #define	NS_RETURN	1
 
@@ -215,6 +225,11 @@ typedef struct {
 #include <sys/cdefs.h>
 
 __BEGIN_DECLS
+
+#ifdef __HAIKU__
+char *	nsswitch_conf_file_path(void);
+#endif
+
 int	nsdispatch(void *, const ns_dtab [], const char *,
 			const char *, const ns_src [], ...);
 
diff --git a/src/system/libnetwork/netresolv/net/nsdispatch.c b/src/system/libnetwork/netresolv/net/nsdispatch.c
index c84d4c950d..19a92d3de6 100644
--- a/src/system/libnetwork/netresolv/net/nsdispatch.c
+++ b/src/system/libnetwork/netresolv/net/nsdispatch.c
@@ -87,8 +87,17 @@ __RCSID("$NetBSD: nsdispatch.c,v 1.37 2012/03/13 21:13:42 christos Exp $");
 
 #include <libutil.h>
 
+#ifdef __HAIKU__
+
+#include <FindDirectory.h>
+int __isthreaded = 1;
+
+#else
+
 #define __isthreaded 1
 
+#endif
+
 extern	FILE 	*_nsyyin;
 extern	int	 _nsyyparse(void);
 
@@ -179,7 +188,12 @@ static pthread_mutex_t _ns_drec_lock = PTHREAD_MUTEX_INITIALIZER;
 /*
  * Runtime determination of whether we are dynamically linked or not.
  */
+
+#ifdef __HAIKU__
+#define	is_dynamic()		(1)	/* accept to load dynamic NSS modules */
+#else
 #define	is_dynamic()		(0)	/* don't bother - switch to ELF! */
+#endif
 
 
 /*
@@ -478,6 +492,19 @@ _nsdbtput(const ns_dbt *dbt)
 	return (0);
 }
 
+#ifdef __HAIKU__
+
+char *
+nsswitch_conf_file_path(void)
+{
+	static char path[256];
+	find_directory(B_SYSTEM_SETTINGS_DIRECTORY, 0, false, path, sizeof(path));
+	strlcat(path, "/network/nsswitch.conf", sizeof(path));
+	return path;
+}
+
+#endif
+
 /*
  * This function is called each time nsdispatch() is called.  If this
  * is the first call, or if the configuration has changed, (re-)prepare
@@ -492,9 +519,11 @@ _nsconfigure(void)
 	static time_t	_nsconfmod;
 	struct stat	statbuf;
 
+	char * path = nsswitch_conf_file_path();
+
 	pthread_mutex_lock(&_nsconflock);
 
-	if (stat(_PATH_NS_CONF, &statbuf) == -1) {
+	if (stat(path, &statbuf) == -1) {
 		/*
 		 * No nsswitch.conf; just use whatever configuration we
 		 * currently have, or fall back on the defaults specified
@@ -521,7 +550,7 @@ _nsconfigure(void)
 	 */
 	pthread_rwlock_wrlock(&_nslock);
 
-	_nsyyin = fopen(_PATH_NS_CONF, "r");
+	_nsyyin = fopen(path, "r");
 	if (_nsyyin == NULL) {
 		/*
 		 * Unable to open nsswitch.conf; behave as though the